Method for cleaning a process chamber

ABSTRACT

Methods and apparatus for cleaning deposition chambers are presented. The cleaning methods include the use of a remote plasma source to generate reactive species from a cleaning gas to clean deposition chambers. A flow of helium or argon may be used during chamber cleaning. Radio frequency power may also be used in combination with a remote plasma source to clean deposition chambers.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of co-pending U.S. patent applicationSer. No. 10/122,481, filed Apr. 12, 2002.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the present invention generally relate to methods ofcleaning a deposition chamber using a remote plasma source.

2. Description of the Related Art

In the fabrication of integrated circuits and semiconductor devices,materials such as oxides are typically deposited on a substrate in aprocess chamber, such as a deposition chamber, such as a chemical vapordeposition (CVD) chamber. The deposition processes typically result indeposition of some of the material on the walls and components of thedeposition chamber. The material deposited on the chamber walls andcomponents can affect the deposition rate from substrate to substrateand the uniformity of the deposition on the substrate.

Several methods of cleaning a deposition chamber have been developed.For example, a remote plasma source can be used to provide a source offree radicals, such as fluorine radicals, that react with depositedmaterial in the deposition chamber, forming volatile compounds that canbe removed from the deposition chamber. However, cleaning a depositionchamber using known remote plasma sources is a time consuming process.Remote plasma sources typically provide free radicals at a flow rate andan intensity that do not result in a level of free radical or ionbombardment that can damage the deposition chamber. However, more timeis required to clean a chamber when a low intensity cleaning processsuch as a remote plasma clean process is used. A lengthy chambercleaning period decreases the number of substrates that can be processedin a given time, since the chamber cannot be used for deposition duringthe cleaning period.

Providing in situ radio frequency (RF) power in the deposition chamberto generate a plasma of cleaning gases is another method that can beused to clean a deposition chamber. Reactive species generated in theplasma bombard and react with deposited material in the depositionchamber, forming volatile compounds that can be removed from thedeposition chamber. The reactive species can also bombard the chamberand remove deposited material from the chamber surfaces. However, thereactive species often damage the chamber due to the energy imparted tothe species in the chamber. Furthermore, the reactive species can reactwith the material forming the chamber lining and create undesirablecontaminants that may land on and harm a substrate undergoing processingin the chamber. For example, if NF₃ is introduced into a chamber, thefluorine ions generated in the plasma can combine with aluminum used asa lining material in the deposition chamber and form particles ofaluminum fluoride.

The removal of contaminating particles from a deposition chamber isbecoming increasingly important because the device sizes are becomingsmaller and aspect ratios are becoming more aggressive. With smallerfeature sizes and more aggressive aspect ratios, the size and number ofcontaminating particles must be minimized in order to maintain theperformance of the device.

Therefore, there remains a need for a method of cleaning depositionchambers efficiently, while minimizing contaminant generation.Additionally, the development of new materials, such as carbon-dopedoxides having low dielectric constants, which can serve as components ofintegrated circuits, has created a need for a method of cleaningchambers that are used to deposit the new materials which can be moredifficult to remove from chamber surfaces than other dielectricmaterials, such as oxides.

SUMMARY OF THE INVENTION

Embodiments of the present invention generally relate to methods ofcleaning a deposition chamber. Deposition chambers used to depositcarbon-doped silicon oxides, as well as other dielectric materials, onsubstrates during semiconductor fabrication can be cleaned using themethods described herein.

In one embodiment, a method of cleaning a processing region of adeposition chamber, comprises generating reactive species, such as freeradicals, in a remote plasma source connected to the deposition chamberby striking a plasma comprising free radicals, such as from a freeradical source, such as a cleaning gas. The plasma is struck using apower of about 2 kilowatts or greater in the remote plasma source. Afterthe plasma is struck, the remote plasma source provides between about 5kilowatts and about 8 kilowatts of power to the struck plasma. Heliumand the activated cleaning gas are introduced into the processing regionof the deposition chamber. The cleaning gas is flowed into theprocessing region at a rate of about 300 sccm or greater. Radiofrequency (RF) power is delivered to the processing region to sustain asufficient number of free radicals to clean the processing region of thechamber. The reactive species of the activated cleaning gas react withdeposited material in the processing region of the chamber to formvolatile compounds that can be removed from the deposition chamber.

In another aspect, a two step chamber cleaning method is provided. Thefirst chamber cleaning step includes providing and sustaining a plasmaof reactive species using a remote plasma source and a source of radiofrequency power within the chamber to be cleaned, i.e., an in situplasma source. The second chamber cleaning steps includes providing andsustaining the plasma of the first step using the remote plasma source,but not the in situ plasma source. In one embodiment, a method ofcleaning a processing region of a deposition chamber comprisesintroducing an inert gas and a cleaning gas into a remote plasma sourceconnected to the deposition chamber. A plasma is struck in the remoteplasma source. The plasma comprises reactive species, such as freeradicals from the cleaning gas. The activated cleaning gas is introducedinto the processing region of the deposition chamber. Radio frequency(RF) power is delivered to the processing region to sustain a sufficientnumber of free radicals to clean the processing region of the chamber.The radio frequency power is then terminated. The chamber is thencleaned for a period of time using the reactive species generated by theplasma that is provided and sustained by the remote plasma source. Bothduring and after the radio frequency power is delivered to theprocessing region, the reactive species of the activated cleaning gasreact with deposited material in the processing region of the chamber toform volatile compounds that can be removed from the deposition chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentinvention are attained and can be understood in detail, a moreparticular description of the invention, briefly summarized above, maybe had by reference to the embodiments thereof which are illustrated inthe appended drawings.

It is to be noted, however, that the appended drawings illustrate onlytypical embodiments of this invention and are therefore not to beconsidered limiting of its scope, for the invention may admit to otherequally effective embodiments.

FIG. 1 is a cross sectional view of one embodiment of a depositionchamber.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention generally provides methods and apparatus forcleaning deposition chambers, such as deposition chambers used in thefabrication of integrated circuits and semiconductor devices. Thedeposition chambers that may be cleaned using the methods describedherein include chambers that may be used to deposit oxides, such ascarbon-doped silicon oxides, and other dielectric materials. An exampleof a chamber that may be cleaned using the methods described herein isthe Producer® Chamber, available from Applied Materials, Inc. of SantaClara, Calif. The Producer® Chamber is a CVD chamber with two isolatedprocessing regions that may be used to deposit carbon-doped siliconoxides and other materials. A chamber having two isolated processingregions is described in U.S. Pat. No. 5,855,681, which is incorporatedby reference herein. The Producer® Chamber has a port to which remoteplasma sources may be attached. A Producer® Chamber with a remote plasmasource, model number 5707024-F, available from Advanced EnergyIndustries, Inc., of Fort Collins, Colo., may be used in embodiments ofthe methods described herein. In the embodiments described herein, oneremote plasma source may be attached to a Producer® Chamber such thatremote plasma source is connected to both isolated processing regions ofthe Producer® Chamber. However, the processes described below may alsobe performed by using two remote plasma sources connected, such as via atee line, to each processing region of the Producer® Chamber, andadjusting the flow rates accordingly. The gas flow rates described belowrefer to flow rates experienced by each of the isolated processingregions. Thus, the gas flow rates experienced by the Producer® Chamberas a whole, i.e., the combination of both of the isolated processingregions, are approximately twice the gas flow rates experienced by eachof the isolated processing regions. While some examples of embodimentsare described with respect to cleaning a processing region of aProducer® Chamber that has two processing regions, the methods describedherein may be used to clean a processing region of a chamber that hasone or more processing regions.

An example of a chamber that has two processing regions is shown inFIG. 1. FIG. 1 shows a cross sectional view of a chamber 100 that isconnected to two remote plasma sources 800. The chamber 100 hasprocessing regions 618 and 620. One remote plasma source 800 isconnected to processing region 618, and the other remote plasma source800 is connected to processing region 620. A heater pedestal 628 ismovably disposed in each processing region 618, 620 by a stem 626 whichextends through the bottom of the chamber body 612 where it is connectedto a drive system 603. Each of the processing regions 618, 620 alsopreferably include a gas distribution assembly 608 disposed through thechamber lid 604 to deliver gases into the processing regions 618, 620.The gas distribution assembly 608 of each processing region alsoincludes a gas inlet passage 640 which delivers gas into a shower headassembly 642.

In various embodiments described herein, the remote plasma source thatis used in the various chamber cleaning methods has a maximum power ofbetween about 5 kilowatts (kW) and about 8 kilowatts. Other prior remoteplasma sources have lower maximum powers. A remote plasma source with ahigher power can generate a hotter plasma, and thus, more radicals toclean the chamber. A remote plasma source with a higher power canprovide enough power to produce a larger number of free radicals than aremote plasma source with a lower power. While some free radicals from aremote plasma source with a higher power may recombine into othermolecules, which are typically not as effective as free radicals forcleaning a chamber, a remote plasma source with a higher power canprovide enough free radicals that a sufficient number of free radicalswill be present to clean the chamber in spite of recombination.

The remote plasma source used in the chamber cleaning methods describedherein is typically capable of delivering and sustaining a free radicalsource, such as a cleaning gas, such as a halogen-containing gas, e.g.,NF₃, at higher flow rates than prior remote plasma sources. For example,the remote plasma source used herein may deliver and sustain a cleaninggas, such as NF₃, at a flow rate of up to and including about 1500 sccm(standard cubic centimeters per minute) to a processing region of thechamber when argon is also flowed to the processing region. The argonmay be flowed into the remote plasma source and then into the processingregion. Some prior remote plasma sources typically deliver and sustain amaximum of about 1000 sccm of a cleaning gas, when argon is also flowedinto the processing region. When argon is not flowed into the processingregion, the remote plasma source used herein may deliver and sustain acleaning gas, such as NF₃, flow rate of up to and including about 1000sccm to the processing region. When argon is not flowed into theprocessing region, some prior remote plasma sources typically deliverand sustain a maximum of about 250 sccm of a cleaning gas. Thus, theremote plasma source used herein can deliver and sustain a free radicalsource, such as a cleaning gas, at a higher flow rate than some priorremote plasma sources. Furthermore, the remote plasma source used hereindoes not require a flow of argon to deliver and sustain a high flowrate, such as between about 1000 sccm and about 1500 sccm, of a freeradical source. Higher flow rates of a free radical source, such as acleaning gas, to the processing region of the chamber to be cleaned aregenerally correlated with faster cleaning times.

Another characteristic of the remote plasma source used in the chambercleaning methods described herein is the remote plasma source's abilityto be used without a flow of argon from the remote plasma source intothe processing region of the chamber. Prior remote plasma sourcestypically require the use of argon to sustain a plasma that is necessaryfor chamber cleaning. The remote plasma source used herein may be usedwith a flow of helium from a separate gas source into the processingregion instead of a flow of argon from the remote plasma source into theprocessing region. Prior remote plasma sources typically do not provideenough power to ionize helium or pure NF₃ to strike a stable helium orNF₃ plasma. Argon is typically easier to ionize than helium or NF₃. Acleaning method using helium flow rather than or in addition to argonflow may be preferred because the chamber is less likely to be damagedby the lighter and smaller helium.

In all of the embodiments of chamber cleaning methods described herein,the cleaning gas may be a halogen-containing gas, such as afluorine-containing gas. Preferably, the cleaning gas is NF₃. Theprocessing conditions and ranges described herein for cleaning gases canbe used with NF₃. Other cleaning gases that can be used include F₂,C₂F₄, SF₆, C₂F₆, CCl₄, and C₂Cl₆.

In one embodiment of a chamber cleaning method, a plasma is struck in aremote plasma source that is connected to a deposition chamber. Argonand a free radical source, such as a cleaning gas, are introduced intothe remote plasma source. Reactive species, such as free radicals, aregenerated in the remote plasma source connected to the depositionchamber. Argon is used to strike a plasma in the remote plasma source. Aflow of argon, such as a flow rate of several hundred sccm, such asabout 300 sccm to about 2000 sccm of argon, for about two seconds, intothe remote plasma source is used to strike the plasma. After the plasmais struck, the flow of argon into the remote plasma source is continued.The plasma comprises argon and free radicals from the free radicalsource, such as a cleaning gas. Preferably, the cleaning gas is orincludes NF₃. Preferably, most or all of the cleaning gas in the plasmais dissociated into free radicals, such as fluorine radicals if afluorine-containing gas is used. The power that is used to strike theplasma is about 2 kilowatts or greater, preferably between about 2kilowatts to about 3 kilowatts, and more preferably, about 3 kilowattsor about half of the maximum power of the remote plasma source. Once theplasma is struck, the remote plasma source delivers about 5 to about 8kilowatts, e.g., about 6 kilowatts of power, to sustain the plasma. Theargon and the cleaning gas that is preferably substantially in the formof free radicals are then introduced into a processing region of thechamber from the remote plasma source. Preferably, the cleaning gas isflowed into the processing region at a rate of about 500 sccm orgreater. More preferably, the cleaning gas is flowed into the processingregion at a rate of between about 500 sccm and about 1500 sccm. Evenmore preferably, the cleaning gas is introduced into the processingregion at a rate of about 1500 sccm. Preferably, the argon is introducedinto the processing region at a rate of between about 500 sccm and about1500 sccm. The free radicals from the cleaning gas react with materialdeposited on the surfaces of the processing region of the depositionchamber to form volatile compounds that can be removed from thedeposition chamber. It is believed that the described gas flow ratesand/or power levels used may contribute to a good, efficient cleaningprocess that minimizes damage to the deposition chamber. It is believedthat the inert gas argon contributes to the cleaning process by dilutingthe free radicals, and thus reducing the amount of recombination betweenthe free radicals. Using this embodiment of a chamber cleaning method,carbon-doped silicon oxides can be removed from the interior surfaces ofa processing region of a chamber. Furthermore, using this embodiment ofa chamber cleaning method, carbon-doped silicon oxides and othermaterials deposited on the interior surfaces of a processing region maybe removed from the interior surfaces at a rate of between about 1μm/minute and about 5 μm/minute. Preferably, the removal rate is betweenabout 2 and about 4 μm/minute. The removal rates are estimated bymeasuring the amount of deposited material that remains on a substratethat has received material during a deposition process in a processingregion of the chamber and lost material during the chamber cleaningprocess. These removal rates are higher than a removal rate of 1.9μm/minute obtained using a less powerful remote plasma source undersimilar conditions. Less time is required for chamber cleaning when acleaning process with a higher removal rate is used.

In another embodiment of a chamber cleaning method, a plasma is struckin a remote plasma source that is connected to a deposition chamber.Argon and a free radical source, such as a cleaning gas, are introducedinto the remote plasma source. Reactive species, such as free radicals,are generated in the remote plasma source connected to the depositionchamber. Argon is used to strike a plasma in the remote plasma source. Aflow of argon, such as a flow rate of several hundred sccm, such asabout 300 sccm to about 2000 sccm of argon, for about two seconds, intothe remote plasma source is used to strike the plasma. The plasmacomprises free radicals from the free radical source, such as a cleaninggas. Preferably, the cleaning gas is or includes NF₃. Preferably, mostor all of the cleaning gas in the plasma is dissociated into freeradicals, such as fluorine radicals if a fluorine-containing gas isused. The power that is used to strike the plasma is about 2 kilowattsor greater, preferably between about 2 kilowatts to about 3 kilowatts,and more preferably, about 3 kilowatts or about half of the maximumpower of the remote plasma source. Once the plasma is struck, the remoteplasma source delivers about 5 to about 8 kilowatts, e.g., about 6kilowatts of power, to sustain the plasma. The cleaning gas that ispreferably substantially in the form of free radicals is then introducedinto the chamber from the remote plasma source. Preferably, the cleaninggas is flowed into a processing region of the chamber at a rate of about300 sccm or greater. An argon flow is not required to introduce thecleaning gas into the processing region of the chamber, and thus, thecleaning gas may be introduced without an argon flow. A radio frequency(RF) power is then delivered to the processing region by energizing anRF source connected between two electrodes in the processing region. Thetwo electrodes will normally respectively comprise the substrate supportmember or susceptor, and the face-plate or “showerhead” through which acleaning gas is distributed into the processing region and which isdirectly connected to the RF power source. Preferably, the cleaning gasis flowed into the processing region at a rate of between about 300 sccmand about 2000 sccm. More preferably, the cleaning gas is flowed intothe processing region at a rate of between about 625 sccm and about 1000sccm. More preferably, the cleaning gas is flowed at a rate of betweenabout 625 sccm and about 875 sccm. Preferably, the radio frequency powerdelivered to the processing region is between about 150 watts and about700 watts. More preferably, the radio frequency power delivered to theprocessing region is about 200 watts. The free radicals from thecleaning gas react with material deposited on the surfaces of theprocessing region of the deposition chamber to form volatile compoundsthat can be removed from the deposition chamber. It is believed that thedescribed gas flow rates and/or power levels used may contribute to agood, efficient cleaning process that minimizes damage to the depositionchamber. It is believed that the radio frequency power contributes tothe cleaning process by sustaining a sufficient number of free radicalsto clean the chamber. Using this embodiment of a chamber cleaningmethod, carbon-doped silicon oxides can be removed from the interiorsurfaces of a processing region of a chamber. Furthermore, using thisembodiment of a chamber cleaning method, carbon-doped silicon oxides andother materials deposited on the interior surfaces of a processingregion of a chamber may be removed from the interior surfaces at a rateof between about 2 μm/minute and about 3 μm/minute. A removal rate of2.6 μm/minute may be obtained using a prior remote plasma source andradio frequency power. However, the prior remote plasma source requireda flow of argon with the plasma. Furthermore, as shown in Table 1, theprior remote plasma source, argon, and radio frequency power process canresult in the formation of an average of 57 contaminating particles,while the combination of the current remote plasma source and radiofrequency power (RF3) may form an average of 19 particles. Cleaningprocesses that produce fewer contaminating particles are preferablebecause such processes reduce the probability that a contaminatingparticle will damage or destroy a substrate in the deposition chamber.

In another embodiment, the chamber cleaning method generally includesthe use of a remote plasma source, helium, and radio frequency powerdelivered to the chamber to maintain a plasma therein. An inert gas,such as argon, and a free radical source, such as a cleaning gas, areintroduced into the remote plasma source. Reactive species, such as freeradicals, are generated in the remote plasma source connected to thedeposition chamber. Argon is used to strike a plasma in the remoteplasma source. A flow of argon, such as a flow rate of several hundredsccm, such as about 300 sccm to about 2000 sccm of argon, for about twoseconds, into the remote plasma source is used to strike the plasma. Theplasma comprises free radicals from the free radical source, such as acleaning gas. Preferably, the cleaning gas is or includes NF₃.Preferably, most or all of the cleaning gas in the plasma is dissociatedinto free radicals, such as fluorine radicals if a fluorine-containinggas is used. The power that is used to strike the plasma is about 2kilowatts or greater, preferably between about 2 kilowatts to about 3kilowatts, and more preferably, about 3 kilowatts or about half of themaximum power of the remote plasma source. Once the plasma is struck,the remote plasma source delivers about 5 to about 8 kilowatts, e.g.,about 6 kilowatts of power, to sustain the plasma. Helium may beintroduced into the chamber via a separate gas line or from the remoteplasma source. The cleaning gas that is preferably substantially in theform of free radicals is introduced into the chamber from the remoteplasma source. Preferably, the cleaning gas is flowed into a processingregion of the chamber at a rate of about 250 sccm or greater. An argonflow is not required to introduce the cleaning gas into the processingregion of the chamber, and thus, the cleaning gas may be introducedwithout an argon flow, except for the argon used to strike the plasma.However, in an embodiment in which a remote plasma source such as theAstron Atomic fluorine generator AX7685, available from MKS ASTeX®Products of Wilmington, Mass., is used, argon is not required to strikethe plasma, and thus, argon is not used in such an embodiment of acleaning process. A radio frequency (RF) power is then delivered to theprocessing region by energizing an RF source connected between twoelectrodes in the processing region. The two electrodes will normallyrespectively comprise the substrate support member or susceptor, and theface-plate or “showerhead” through which a cleaning gas is distributedinto the processing region and which is directly connected to the RFpower source. Preferably, the cleaning gas is flowed into the processingregion at a rate of between about 250 sccm and about 2000 sccm. Morepreferably, the cleaning gas is flowed at a rate of between about 250sccm and about 1250 sccm. Preferably, the helium is introduced into theprocessing region at a rate of between about 125 sccm and about 2500sccm. Preferably, the radio frequency power delivered to the processingregion is between about 150 watts and about 1000 watts, such as betweenabout 250 watts and about 350 watts. The free radicals from the cleaninggas react with material deposited on the surfaces of processing regionof the deposition chamber to form volatile compounds that can be removedfrom the deposition chamber. It is believed that the described gas flowrates and/or power levels used may contribute to a good, efficientcleaning process that minimizes damage to the deposition chamber. It isbelieved that the inert gas helium contributes to the cleaning processby diluting the free radicals, and thus reducing the amount ofrecombination between the free radicals. It is also believed that thehelium contributes to the cleaning process by bombarding the depositionchamber and removing deposited material from the chamber surfaces. It isbelieved that the chamber receives less damage from helium bombardmentthan from bombardment with heavier and larger argon typically used inother methods of chamber cleaning. Furthermore, it is believed that theradio frequency power contributes to the cleaning process by sustaininga sufficient number of free radicals to clean the chamber. Using thisembodiment of a chamber cleaning method, carbon-doped silicon oxides canbe removed from the interior surfaces of processing region of a chamber.Furthermore, using this embodiment of a chamber cleaning method,carbon-doped silicon oxides and other materials deposited on theinterior surfaces of a chamber may be removed from the interior surfacesof a processing region of a chamber at a rate of between about 2μm/minute and about 5 μm/minute.

Optionally, a chamber cleaning embodiment may further include a periodof cleaning in which the radio frequency power in the chamber is notused. After the helium and the cleaning gas are introduced into theprocessing region of the chamber and a radio frequency power is appliedto the processing region of the chamber, as described above, the radiofrequency power is terminated. The chamber is then treated for a periodof cleaning using a flow of argon rather than helium. The flow of heliumis terminated, and argon is introduced into the remote plasma source.Argon and cleaning gas are then flowed from the remote plasma sourceinto the processing region. Preferably, the cleaning gas is flowed intothe processing region at a rate of between about 250 sccm and about 1250sccm when the argon is introduced into the processing region.Preferably, the argon is introduced into the processing region at a rateof between about 250 sccm and about 2500 sccm. Using this embodiment ofa chamber cleaning method, carbon-doped silicon oxides and othermaterials can be removed from the interior surfaces of a processingregion of a chamber. Furthermore, using this embodiment of a chambercleaning method, carbon-doped silicon oxides and other materialsdeposited on the interior surfaces of a chamber may be removed from theinterior surfaces of processing region of a chamber at a rate of betweenabout 2 μm/minute and about 4 μm/minute. TABLE 1 Etch Rate NF₃ CleanEst. NF₃ RPS Unit and on Substrate Flow Rate Time Through- UsageParticles Clean Recipe (μm/min) (sccm) (1 μm) put wph (scc) (>0.2 μm)Prior RPS/Argon 1.9 1000 360 s 12.5 6000 29.7 Prior RPS/Argon & RF 2.6750 240 s 16.8 3000 57 RPS/Argon 3.1 1000 240 s 16.8 4000 27RPS/Helium/RF1 2.78 625 240 s 16.8 2083 16 RPS/Helium/RF2 2.8 750 240 s16.8 2250 6 RPS/RF3 2.8 875 250 s 16.5 2650 19

Table 1 shows a comparison of chamber cleaning results obtained using aprior remote plasma source (prior RPS), such as an Astron® Type AX7650reactive gas generator from MKS ASTeX® Products of Wilmington, Mass.,and a remote plasma source (RPS) and methods described herein, such as aremote plasma source, model number 5707024-F from Advanced EnergyIndustries, Inc., on a chamber having carbon-doped silicon oxidedeposited on its interior surfaces. The RPS/Argon results were obtainedusing 1000 sccm of NF₃, and 1000 sccm of argon. The RPS/Helium/RF1results were obtained using 625 sccm of NF_(3,) 1250 sccm of helium, andan RF power of 350 Watts. The RPS/Helium/RF2 results were obtained using750 sccm of NF_(3,) 500 sccm of helium, and an RF power of 350 Watts.The RPS/RF3 results were obtained using an RF power of 200 Watts. Theremote plasma source, model number 5707024-F from Advanced EnergyIndustries, Inc. and processing conditions described in embodiments ofthe invention yielded a faster cleaning process than the prior remoteplasma source, as reflected by the etch rate of the substrate, i.e., therate at which deposited material is removed from a substrate in aprocessing region of the chamber during cleaning, the clean time, i.e.,the time required to remove 1 μm of material deposited on the processingregion surfaces, and the estimated throughput (wafers per hour (wph)),i.e., the number of substrates that can be processed in the chamber withthe chamber cleaning process between the processing of each substrate.Furthermore, the present cleaning methods result in the creation orpresence of fewer particles greater than 0.2 μm than prior cleaningmethods. The present cleaning methods also require fewer standard cubiccentimeters (scc) of NF₃ than prior cleaning methods. The consumption ofless NF₃ is desirable because of the typically high cost of NF₃.

Examples of embodiments will now be described.

EXAMPLE 1

Several hundred sccm of argon was flowed for about two seconds to strikea plasma in two remote plasma sources, model number 5707024-F fromAdvanced Energy Industries, Inc., connected to a processing region of aProducer® Chamber having experienced a deposition of about 1 μm of BlackDiamond™ film, a silicon oxycarbide film available from AppliedMaterials, Inc. of Santa Clara, Calif., deposited on a substrate withinthe chamber. NF₃ was also introduced into the remote plasma sources.After the plasma was struck, the remote plasma sources delivered about 6kilowatts of power to the struck plasma. The plasma included freeradicals from the NF₃. The NF₃ was flowed into a processing region ofthe deposition chamber at a rate of about 900 sccm. Helium was flowedfrom a separate gas line into the processing region at a rate of about500 sccm. A radio frequency power of about 250 Watts was delivered tothe processing region. The spacing between the electrodes, i.e., theshowerhead and the substrate support member, was about 400 mils. Thechamber was cleaned for about 200 seconds. A substrate having BlackDiamond™ film deposited on its surface was present in the chamber duringcleaning so that the amount of Black Diamond™ film removed from theprocessing region surfaces could be estimated. Black Diamond™ film wasremoved from the substrate at a rate of about 3.2 μm/min.

EXAMPLE 2

Several hundred sccm of argon was flowed for about two seconds to strikea plasma in two remote plasma sources, model number 5707024-F fromAdvanced Energy Industries, Inc., connected to a processing region of aProducers Chamber. NF₃ was also introduced into the remote plasmasources. After the plasma was struck, the remote plasma sourcesdelivered about 6 kilowatts of power to the struck plasma. The plasmaincluded free radicals from the NF₃. The NF₃ was flowed into theprocessing region at a rate of about 900 sccm. Helium was flowed from aseparate gas line into the processing region at a rate of about 500sccm. A radio frequency power of about 250 Watts was delivered to theprocessing region. The spacing between the electrodes of the processingregion of the chamber was about 400 mils. The chamber was cleaned forabout 140 seconds. The radio frequency power was terminated. The flow ofhelium into the deposition chamber was terminated. NF₃ was flowed intothe processing region from the remote plasma sources at a rate of about750 sccm. Argon was flowed from the remote plasma sources into thedeposition chamber at a rate of about 500 sccm. The spacing was about260 mils. The chamber was cleaned for about 60 seconds.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

1. A method of cleaning a processing region of a deposition chamber,comprising: striking a plasma at a first power with argon in a remoteplasma source connected to the deposition chamber; introducing acleaning gas into the remote plasma source; generating reactive speciesof the cleaning gas in the remote plasma source; introducing thecleaning gas and the argon into the processing region; and removingcarbon-doped silicon oxide deposited on interior surfaces of theprocessing region.
 2. The method of claim 1, wherein the carbon-dopedsilicon oxide is removed from the chamber at a rate of between about 2μm/minute and about 4 μm/minute.
 3. The method of claim 1, wherein thefirst power is between about 2 kilowatts to about 3 kilowatts.
 4. Themethod of claim 3, further comprising increasing the power to a secondpower of between about 5 kilowatts to about 8 kilowatts after the plasmais struck.
 5. The method of claim 1, wherein the cleaning gas comprisesNF₃.
 6. The method of claim 1, wherein the cleaning gas is flowed intothe processing region at a rate of between about 500 sccm and about 1500sccm.
 7. A method of cleaning a processing region of a depositionchamber, comprising: striking a plasma at a first power with argon in aremote plasma source connected to the deposition chamber; increasing thepower to a second power of between about 5 kilowatts to about 8kilowatts after the plasma is struck; introducing a cleaning gascomprising NF₃ into the remote plasma source; generating reactivespecies of the cleaning gas in the remote plasma source; introducing thecleaning gas and the argon into the processing region; and removingcarbon-doped silicon oxide deposited on interior surfaces of theprocessing region.
 8. The method of claim 7, wherein the carbon-dopedsilicon oxide is removed from the chamber at a rate of between about 2μm/minute and about 4 μm/minute.
 9. The method of claim 7, wherein thefirst power is between about 2 kilowatts to about 3 kilowatts.
 10. Themethod of claim 7, wherein the cleaning gas is flowed into theprocessing region at a rate of between about 500 sccm and about 1500sccm.
 11. A method of cleaning a processing region of a depositionchamber, comprising: striking a plasma with argon in a remote plasmasource connected to the deposition chamber; introducing a cleaning gasinto the remote plasma source; generating reactive species of thecleaning gas in the remote plasma source; introducing the reactivespecies of the cleaning gas and helium into the processing region; andremoving carbon-doped silicon oxide deposited on interior surfaces ofthe processing region.
 12. The method of claim 11, wherein the cleaninggas is a halogen-containing gas.
 13. The method of claim 11, wherein thecleaning gas is a fluorine-containing gas.
 14. The method of claim 11,wherein the cleaning gas comprises NF₃.
 15. The method of claim 14,wherein the plasma is sustained at a power of between about 5 kilowattsto about 8 kilowatts after the plasma is struck.
 16. The method of claim15, wherein the reactive species of the cleaning gas are flowed into theprocessing region at a rate of between about 250 sccm and about 2000sccm.
 17. The method of claim 11, wherein a flow of argon at a flow rateof between about 300 sccm and about 2000 sccm into the remote plasmasource is used to strike the plasma.
 18. The method of claim 11, whereinthe helium is introduced into the processing region from the remoteplasma source.